© Fernando Caracena, 2017
The Anticipated Future
Go back to old articles written in the 1950s, and before. See what they wrote about the future and science. You will see wonders that were expected to happen in everyday life by now. Although there has been much progress and some of those wonders have been realized, many of the wonders predicted back then are not realized now. The Dick Tracy wristwatch communicators having global reach have become common, but we do not see traffic moving in three dimensions, or people spending a few days on the moon. We do not see the kind of personal wealth that the futurists foresaw. Where is the personal wealth gained by the fantastic growth in productivity of the average worker? Were the early predictions off base, or did something else intervene and forestall the magnificent future for humanity they saw coming. If so, what are the obstacles to regaining a bright future for humanity. How can we get back on track?
Is the a Great Purpose for Humanity ?
We are a restless species, which is constantly reaching out, finding new challenges, and exploiting new discoveries. Suddenly, we find ourselves rapidly filling our planet. Experts tell us that we can no longer participate in the great exponential expansion that has characterized the growth of our species. They tell us that we have to scale back our expectations and learn to live in a limited environment. Yet, we know in our hearts, that humanity has a destiny to extend its habitat beyond the planet earth. When we look out upon the stars we see the great challenge is the vast space beyond Earth that affords humanity the great room for challenge and exponential expansion. Our future is in the stars.
Are there Other Civilizations Out There?
Enrico Fermi(1901–1954) the famous physicist called attention to "the apparent contradiction between the lack of evidence and high probability estimates for the existence of extraterrestrial civilizations", a question now known as the Fermi paradox. To all appearances, we humans exist in a universe devoid of extraterrestrial, intelligent lifeforms. Fossil evidence indicates that life appeared on the Earth as soon as conditions supported its existence. There is even evidence that microbes existed on Mars a long time ago from the Allan Hills, Antarctica find on December 27, 1984. Scientists have proposed a variety of reasons why there are apparently no extraterrestrial civilisations out there. I would make the estimates of lack of civilizations based on surface evidence.
Consider that astronomical distances are enormous. Our closest star, the Sun, is 93 million miles away, from which light takes about 8 minutes to reach us. Astronomers use the speed of light to establish the enormous astronomical distance scales. Our Sun on this way of reckoning is about 8 light minutes away. After our Sun, the closest star is in a cluster of three stars called Alpha Centauri, from which Proxima Centauri is the nearest to us at 4.37 light years.
Also consider that Guglielmo Marconi succeeded in sending the first radio transmission across the Atlantic Ocean on December 12, 1901. This signal was very simple, a Morse code of the letter "s", which was sent from Poldhu in Cornwall, England, to Newfoundland, Canada. This signal by now has travelled out about 116 light years, and an answer may be on the way back not yet reaching us. What we can say about our first foray into electromagnetic communications, which are at light speed, is that in a sphere about 58 light years in radius, there was no one there to answer our signal of "s" in Morse code. What would the expected answer be? Maybe they are still trying to decipher the cryptic Morse code message of "..." .
So What is our destiny?
What is the most conservative scientific statement that we can make based on the above observations about the apparent lack of extraterrestrial civilizations? Because of the finite speed of light and no signal is thought to be able to travel faster than the speed of light, we are limited on what we can say about what is present or absent in the universe based on detection of its presence. The human race is estimated to have existed only several hundred thousand years. Most of that time, we would have not done anything to call much attention to our presence on this planet. It is only a few thousand years since the people of Egypt built the pyramids. This means that if perchance they were seen in extraterrestrial telescopes, the light signaling the presence of these mega structures will not have reached farther than a few thousand (k) light years (ly). Further, the distance out at which the pyramids could be detected on Earth by a distant optical telescope is restricted by the resolving power of such a device, which is probably much less than a few thousand light years.
Perhaps Extraterrestrials have detected out Radio Signals?
Our first attempts at generating electromagnetic signals (radio waves) date back only 116 years to Marconi' s first transmission. We could not have heard from any extraterrestrial civilization outside a detection and answer radius, of half of the distance of our outgoing signal of about 116 light years making the answer radius restricted to about 58 light years. What we can say from this is that nobody else is out there within about 50 light years who can decipher our electromagnetic signals and cares to answer them. Consider that our galaxy is a disk estimated to have a diameter of 100 to 180 thousand light years (kly) and a thickness of 2 kly, I think that you would agree that we have not sampled enough of the universe to sufficiently to make pronouncements about the presence or absence of extraterrestrial civilizations in it.
Suppose human development represents about the average rate of development of a sentient species from the emergence of life on a planet. The latest astronomical findings are that there are 8.8 Billion Earth-like planets in our galaxy (8.8 X 109). Taking the top estimate for the size of our galaxy as a diameter of 180,000 ly and its thickness as 2,000 ly, the volume of our galaxy turns out to be about 5.9 x 1013 cubic ly. Dividing the total volume by the estimate of the number of Earth-like planets, we find that each such planet is on that average surrounded by about 5.09 x 1013 / 8.8 X 109 cubic ly of space devoid of Earth-like planets, which is about 5800 cubic ly. Were these planets distributed regularly on a grid throughout the volume of the galaxy, the cub root of this number would yield the average separation of these planet. This number turns out to be about 18 ly. At this distance, we should have already heard from our extraterrestrial neighboring civilization.
Perhaps then, Earth-like planets are distributed rather more sparsely than the average in our neighborhood and the nearest such planet is much higher than the estimated distance of 18 ly. An alternative is that humans have developed faster than the sentient beings surrounding us. In that case, we have a large volume of space that we can expand into unopposed, where we are more likely to find primitive humanoids than advanced civilizations.
Obviously, the future role of mankind is to seed and populate all regions in space that we can see, which are devoid of sentient beings. Before we can do that, however, we must learn to be able to get along with our selves and develop fair forms of self government. We also need to learn how to treat our less developed brothers better than we have been able to in the past. We have several important lessons to learn as a species before we are ready to go out among the stars and began to fill the galaxy.